A man walks into a Japanese Burger King and orders a bacon burger laden with 1050 pieces of swine...

No, this isn't the beginning of a bad joke - it actually happened, and there's a viral YouTube video to prove it.

In the video, we a see a guy sit down at a table and unwrap a mountain of bacon loosely held together by two buns and some nominal garnishment. He measures the mound of pork against his iPhone. He bows his head in a short prayer and starts stuffing his face.

Eventually he takes an alternating-hand approach - a bite of bacon from his right, a bite of bun from his left. After making a valiant effort, but relatively small dent in the monstrosity before him, the man retires to a bathroom with a decidedly queasy look on his face.

The video has been viewed over 700,000 times since it was posted online on Tuesday, and been picked up with short accompanying blurbs in many corners of the internet.

But there have so far have remained a number of unanswered questions: Who is this hero of gluttony? Why did he do it? Did he survive? Mashable Skyped into Japan to learn more.

Steven Simonitch is a 24-year-old American living in Nagano Prefecture. An English teacher by day, he moonlights as a senior writer for the news site rocketnews24.com, which posted the bacon video.

The man in the video is Simonitch's colleague at the site. Despite working with him and considering him a friend, Simonitch still knows our mysterious hero only by the name Sato-san - or, Mr Sato.

Mr Sato is 38. He's single. He doesn't speak much English, like most of the website's staff. "He's kind of our guinea pig," Simonitch says. "If we have some random crazy idea we just say, 'Let's have Mr Sato do it.'"

Mr Sato recently shaved his head like this. He's also eaten this, as well as another burger topped with a piddling 105 pieces of bacon. When the iPhone 4 was released in Japan in 2010, he gained fame by waiting in line dressed up like this.

Simonitch wasn't present when Mr Sato took on the 1,050-piece bacon burger, but his colleagues tell him "the stench of bacon just filled the whole room. They're probably going to have to scrub out the walls." As for Mr Sato's health, Simonitch says he's doing fine after the showdown.

Mr Sato helped launch the Japanese version of the site in 2008, and today it employs him and several others full time. It's become huge in Japan, ranked among the country's top 200 websites. But Simonitch says Mr Sato and company have recently been looking to get more traction with English readers. Mission accomplished.

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